1. Field of the Invention
The present invention relates to levels for use in masonry, carpentry or in many other fields, such as architecture and interior design. More particularly, the present invention is directed toward an adjustable plumb level having a 360.degree. rotational, replaceable leveling mechanism.
2. Description of the Related Art
Adjustable levels have been known for a considerable time, but these levels lacked the necessary versatility to be used for long periods of time as either a plumb or a level. This required that the person using both levels and plumbs have more than just a single piece of equipment, and replace this equipment at fairly regular intervals.
For example, Clarke in British Pat. No. 771,735 teaches a level with a 360.degree. rotatable vial. Grooves L are provided on sleeve B in which the vial is mounted. The vial A is held in position by a catch, which includes a slide M movable by a spring N. The slide engages the grooves provided on the sleeve. Vial A is positioned in a desired position by way of the user setting the vial in the desired position after moving the slide backwards so as to release it from the groove in which it is set. The slide M moves by way of "finger pressure". Thus, the accuracy of this device is compromised as the user has to carry out the positioning process by actually moving the vial and slide with his or her hands.
Many levels have been disclosed where the vial may be tipped slightly in order to level the vial. However, as these models, such as those disclosed in U.S. Pat. No. 1,703,006 to Jay and U.S Pat. No. 516,024 to Schaefer, only move the vial several degrees, it is impossible to use the level when large variations from horizontal must be accounted for.
Due to the inherent inaccuracies of levels and plumbs, it is not uncommon for buildings to be built slightly askew. Minor errors in construction will force the next person that builds an adjacent or above structure to build the adjacent structure also at a slight tip to compensate for the skew in the first building or part. Thus, it is desirable to have an adjustable level that can be calibrated for perfect level or plumb and can be used in either a vertical or a horizontal position, i.e. as either a plumb or a level, without requiring the use of a great number of parts.